Re: Shortcut logicals (was: Re: F200x )

[Martin Krischik <martin@krischik.com>]

Adrien Plisson wrote:

> Martin Krischik wrote:
>> Christoph Grein wrote:
>>>You'll find
>>>relation and relation gives an expression,
>>>relation and then relation also gives an expression.
>>>But there is no syntax rule to combine an expression with a relation.
>>>You can only combine a parenthesized expression (a primary) with a
>>>relation.
>> 
>> 
>> Sure, you are right. But that rule means that:
>> 
>>  X or Y and Z
>> 
>> is not valid either. Not that I ever noticed - I would always use '()' on
>> such a term.
> 
> it isn't valid. GNAT 3.15p says: mixed logical operators in expression.
> 
> See RM Introduction - design goals (ￜ7):
> "error-prone notations have been avoided"
> 
> and this construct is error-prone (especially if you are used to code
> in other languages than Ada, since each language has its own different
> operator precedence). the use of parenthesis clarifies the expression
> and leverages any ambiguities.

I fully agree with you here - and most Ada users will do as well. I would
use () in C and C++ as well - for clarity.

This is of corse a cross post with comp.lang.fortran and I wonder how they
see our solution to the problem. Is it suitable for Fortran 2003 as well or
do they need another solution?

With Regards

Martin
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